Are Stock Brakes Really That Bad?

[ed1948]

From what I've seen many people upgrade their brakes. I haven't had much seat time in my Monte but I do know pedal effort is quite high. I will only drive normally(no racing or high speed) on city and highway and I believe fade will not be an issue. So, the question is: will the stock brakes work well enough to be confident in their stopping ability. I have gotten spoiled by today's modern all disk ABS systems.

 

[DoubleV]

I've never had an issue with stock brakes. Seem fine to me.

 

[L67ss]

Are they crappy by themself? No. Do they suck compared to newer brakes even from the mid 90s? Yup

 

[Jeff L]

I've never had an issue with stock brakes. Seem fine to me.

Same here. All I have done in 30+ years is have the brakes done when pads needed replacing and never had a brake issue beyond normal maintenance.

 

[TURNA]

Once you put a little power under the hood these brakes suck.

Especially the 78-81 small cast iron master cylinder and single diaphragm booster.

The double diaphragm and larger aluminum Monte SS type setup is a nice "parts store" improvement.

But then the you can install a larger master as long as it meets these specs

Primary Port Size:1/2 x 20
Reservoir Material: Plastic
Secondary Port Size: 9/16 x 18
Bore Diameter (N-1): 40mm
Bore Diameter (N): 1.125"
Master Cylinder Material: Aluminum

Some B- Bodies and 81 Trans-Am with front disk, rear drum meet these specs.

 

[pontiacgp]

if you have questions about the stock brake capabilities head to an asphalt circle track and watch the G body stock cars on the track. They have to use stock brake set up in the lower classes of race cars and those brakes will be glowing red hot all race and be ready for the next race. I put in a set of EBC pads with new stock rotors, broke them in properly and those brakes saved me some body work a few times.

 

[Clone TIE Pilot]

GM was also a little weird with brake setups among different g body models. 1986 Monte Carlo SSs only had single diaphragm boosters while base n/a V6 Regals had dual diaphragm boosters despite having much weaker engines than SSs. A big help for stock brakes is using quality rotors, pads, drums, and shoes. Cheap store brand parts often are sub standard quality, had a set of store brand rotors warp just from normal driving. Good quality brake parts make a difference. Simple bolt on upgrades are front calipers with oversized pistons and larger S10 rear drum cylinders. After than things start to get complicated and expensive.

 

[ed1948]

Thanks for your tips and advice. I can take the 34 layers of bubble wrap around my car off now, I guess.

 

[malibudave]

When dealing with 30 to 40 year old brakes, it may be best to replace the stock rubber brake lines front and rear. Over time, the rubber will deteriorate and the lines will start to balloon with pressure reducing you braking performance and give you a softer pedal. Replace rubber lines with new rubber lines or aftermarket stainless steel braided flex lines front and rear.

Another thing is changing out your fluid. Over just a few years, you fluid will collect moisture and reduce your braking performance. You will notice a difference in braking performance when you just change your fluid if your fluid is fairly old.

If you running rear drum brakes, make sure the pads are adjusted out against the drum correctly. Make sure the adjuster is in good working order as your rear shoes will adjust every time you use your brakes in reverse.

If you still have a soft pedal, you master cylinder may not be holding pressure. The only way to test this is to pull it off the car and bench bleed it using the plug method.

Bleeding your master cylinder using the plug method

1. If the master cylinder is coming off the car, dispose of the brake fluid in the reservoir.

2. Mount your new or used master cylinder in a vise.

3. Use the appropriate size plugs for the outlets. For GM this is ½-20 inverted flare for the rear port of the master cylinder and 9/16-18 inverted flare for the front port.

4. Fill the master cylinder with fresh brake fluid.

5. Slowly cycle the master cylinder piston with a NON sharp, NON pointed rod. NO flat head or phillip screw drivers.

6. Once the piston stops moving, the master cylinder is now bled of all the air. There should only be a slight amount of movement in the piston (Less than a 1/16 of an inch).

7. After the piston stops moving, apply pressure on the back of the master piston and hold for 45 seconds. If the piston starts to slowly move down the piston, your master cylinder needs to be replaced or rebuilt.

8. If your master cylinder holds pressure, you are good to mount it to the car and bleed the rest of the system.

Using the plug method to bleed your master cylinder does two things. First, I gets all the air out of the master cylinder. Second, it tests the master cylinder to see if it is bad.

 

[pontiacgp]

Thanks for your tips and advice. I can take the 34 layers of bubble wrap around my car off now, I guess.

your car drove out of the factory about 30 years ago and it appears that the brakes worked to keep the car from plowing into anyone in all those years so I think they must be good brakes. One thing I think people overlook is the back brakes. It's true the front brake do most of the braking but without good back brakes the ability to stop is diminished. Anyone here who has a standard transmission can tell you that the brakes work much better when you put the car in neutral coming to a stop for a light or stop sign. If anyone wants to see the difference put your car in neutral and apply the brakes. With poor or out of adjustment rear brakes there is nothing to work towards the power that is still be put to the rear wheels and the front brakes are taking the punishment.